The detailed kinetic and chemical mechanism of several enzymes are being studied including serine hydroxymethylase, muconate lactonizing enzyme, and DNA polymerase. Relevant non-enzymatic model systems are being studied mechanistically relevant to the roles of the cofactors pyridoxal-5'-phosphate and tetrahydrofolate, as well as the apoproteins, per se, in catalysis. BIBLIOGRAPHIC REFERENCES: "Equilibria and Kinetics of N-Hydroxymethylamine formation from Aromatic Exocyclic Amines and Formaldehyde: Effects of Nucleophilicity and catalyst strength upon mechanisms of catalysis of Carbinolamine Formation". Abrams, W.R., and Kallen, R.G., J. Amer. Chem. Soc., 98, (1976), in press. "Estimates of Microscopic Ionization Constants for Heteroaromatic Exocyclic Amines including Purine and Pyrimidine Nucleotides and Amides based upon a Reactivity-basicity correlation for N-Hydroxymethylation Reactions with Formaldehyde". Abrams, W.R., and Kallen, R.G., J. Amer. Chem. Soc., 98, (1976), in press.